For anyone playing Vampire Crawlers, some tips that I picked up along the way.
Wild cards are your friends. On top of what they actually do, they allow you to continue combos for a long time, which is something very important as the bosses get harder.
Once you unlock him, Korchi is your friend and should never leave your party. Revivals are a very nice option to have if you have one or two bad draws, and having a way to build up revivals is only really doable with him in your party.
Make sure to unlock having multiple crawlers in your party ASAP. Their synergy is very useful.
Once you unlock her, Christine is a very big help. Her ability to disarm enemies when she's active and a certain card color is played made the final boss go from seemingly impossible to "didn't even hit me once in the final phase".
Make sure you have at least one card with Freeze in some way. Later bosses have a timer that lets you know EXACTLY when they are going to attack, so as long as you have a card with Freeze, you can stop them at the appropriate time. Might have to break combo for it, but wouldn't you rather do that than take a 30+ hit to the face?